The Menace of Diabetic Gangrene - Can It Be Prevented?

Robert Frykberg, DPM, MPH discusses the traditional and current approaches to gangrene prevention and treatment. Dr Frykberg emphasizes the success of a patient centered, multi-disciplinary approach and cites articles and studies as support.

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Robert Frykberg
has no relevant financial relationship(s) to disclose.

Lecture Transcript

Male Speaker: Hopefully got a good overview of the broad spectrum of wound care theories, advanced therapeutics, basic therapeutics and now the importance of considering the role for malignancies for you chronic non-healing wounds. I think every patient’s greatest fear when they have diabetes is that of developing gangrene and having amputations. This goes back many, many years so I wanted to speak to about the menace of diabetic gangrene and the question can it be prevented? These are my disclosure as of before, we have several learning objectives to learn about three causes of diabetic gangrene. Recognize various pathways that precede development as well as effective preventive strategies. From ancient times it has been said “What has been will be again, what was done will be done again and there’s nothing new under the sun” from Ecclesiastes. And that’s true, nothing that we are seeing here, nothing that we’re really talking about except for advance therapeutics is really anything new. And to that point, I refer you to one of my favorite papers by Elliot Joslin in 1934. Menace of diabetic gangrene from which I’m developing this topic. Joslin said “Diabetic gangrene has been increasing as a menace to my patients.” Now isn’t that insightful? I think many of us here, certainly to those who work in the V.A. system can say, “Gangrene has been increasingly a menace to my patients. I see it every single day. I’m astounded how common this is and therefore it has come upon us to find ways that we can hopefully prevent it. We’ll never cure it. We’ll never eliminate it totally but we need to focus on prevention as always. That’s why we’re here. My first talk early this morning was really focusing on learning underlying risk factors so that you can effectively intervene and prevent the consolation to a final pathway leading to amputation. So going back to Joslin’s journal paper and I recommend that you all get this. It’s all fairly available. Fabulous paper and it really is quite insightful. He was speaking about his own experiences in the late 20s just at the age of insulin. New England Deaconess Hospital where I and several other colleagues in this room had trained years ago. And he focused on his experiences in 1933 where he had 972 diabetic patients. Boston was a small town back on those days, so he had quite a following. This was the man who started the famous Joslin Clinic that we’re all familiar with. And at that time, he said he had 32 deaths and 16% of his deaths were from gangrene. As you can see his patients weren’t that old, they were about 67 years old, the duration of 10 years. Good percentage of his deaths were due to diabetic coma which we don’t often see now. But remember this was just at the age of insulin and Joslin was one of the very first people who have ever used insulin in this country. But he did note that he had 51 amputations for gangrene and infection. But look at the spectrum here, 27% were toe amputations out of the 51 and 73% were major amputations. So this was a very, very significant problem for him. It disturbed him greatly that patients were coming in with this end-stage complication. He determined that the ideology of gangrene was arteriosclerosis of what we call now PAD, peripheral arterial disease, infection, delay in treatment, poor diabetes control and trauma. Trauma then was heat or heating pads, hot soaks, excessive cold or inadequate shoes. Now is anything different back then than it is today? Not at all. So it’s very telling that he was discussing the same problems over 70 years ago and we’re still seeing the same problems even today. Joslin also recommended certain aspects for the treatment of diabetes and gangrene or to help in the prevention of gangrene. He recognized what he called the troika for medical treatment. The key facets of diabetes control that he developed from the early 20th Century up until the age of insulin. That was good diet and nutrition which was their mainstay of therapy early on. Exercise also as well as insulin with multiple small doses, just like we give today. Multiple does during the day.

[5:00]

But he was a strong proponent of surgical treatment as well. Joslin was one of first physicians in the United States if not the world to practice with a multi-disciplinary environment where he had his own surgical team, his own nurses, his own chiropodist, his own team that will see every one of his patients. The famous McKittrick [phonetic] brothers who went on to develop the classical TMA paper where his surgeons, his special team of surgeons. And they practice on their premise that early aggressive surgery was always the best way to approach this limb threatening and life threatening problems. So they did pump drainage of infection, they performed often guillotine amputations as needed to drain infections. Recognizing that these amputations could be lifesaving as well as actually cost savings because they didn’t have home nursing back then. People tend to stay in the hospital for weeks or months at a time until they were cured. His indications for operation and in those days operation mainly meant amputation at some level was gangrene and are painful or pulseless foot. He determined that pulses were the best indicator of circulation. This was the days before noninvasive arterial castings and TCPO2. So as good clinical examinations and palpation of pulseless or pain and a pulseless foot. And also an indication of osteomyelitis and what did Joslin used to test for osteomyelitis, a probe test. He was one of the first to import great probing of bone as one of these clinical indicators for osteomyelitis. He also believed that recurrent ulcers in the callous or under callous good indication that it might be osteomyelitis and they often require amputation. Now we would not amputate for these reasons but in those days they just amputate as part of their limb salvaging strategy for foot surgery. And of course amputations were required. Guillotine amputations in particular for extensive reinfections that were really a surgical emergency i.e. like necrotizing fasciitis or septic feet - septic soft tissue. Necrotizing infections that require urgent guillotine amputations in order to save one’s life as well as control infection. But he also focused in this one article on prevention of gangrene as well. And as you might suspect, he prescribed good diabetes control. He prescribed what he called cleanliness which really amounted to daily inspection of patient’s daily self-inspection. Avoidance of trauma, we’ve mentioned earlier that we recognized the trauma as one of the inciting factors for diabetic foot ulceration. Well he recognized that as well and he wanted to avoid trauma such as hot soaks and shoes. He specifically mentioned hot soaks, heating pads and that kind of thing as well as improperly fitted shoes. He first prescribed an amputee support group; education. Just like we’re seeing now people were talking about these things. So he was a big proponent of education not just of physicians but also of patients. And lastly and perhaps foremost for many of us in this room, he prescribe chiropody. Podiatry care as being an integral part of his team. So back in the 20s, Dr. Joslin had his own chiropodist or podiatrist. I believe his name was Dr. Kelly who was very well regarded, very important member of the team. Who took it upon himself to take care of these patients, some in the acute stage, but in the preventive stage, preventing problems and practicing prevention with foot care, nail care, et cetera. So nothing is new under the sun. This was present back in Boston, back in the late 20s and the early 30s. He prescribed for the multidisciplinary approach as I said. With a physician meaning an internist or diabetologist, a surgeon, a chiropodist, a dietician, always a part of the team, a physical therapist was part of the team, as well as the nurse. In the old days he had a diabetes nurse, a wound care nurse who would follow around, make rounds every day and do the dressings. Each and every day, they’d make their own rounds with the team or without the team doing twice a day or three times a day, dressings is prescribed but usually by these surgeons, so multidisciplinary management, nothing new. We’re just starting to embrace that now around the world. So what has changed in 79 or so years? Well we certainly understand the underlying pathophysiology of diabetes as well as the complications. And I think it’s fair to say we understand the complications and the disease itself much better than Joslin was able to back then although he was very insightful in this regard.

[10:00]

Are we even better in treating diabetes? We certainly have more agents at our disposal. But remember even Joslin prescribed multiple daily doses of insulin and good education, good nutrition, exercise, good diet control. Are we better at preventing and treating diabetes complications? Well hopefully we are. I think we are probably better at treating them with our knowledge, better knowledge with the underlying pathophysiology. And that has come through much study as you’ve heard of today. We saw this slide already so I don’t want to belabor this. We just recognized that 60% of non-traumatic lower extremity amputations occur in the United States encompassing only about 78% of our population. And we know that the costs are high, we know that it takes a tremendous toll on our diabetic patients and negatively impacts on their survival. It’s makes good sense for us to try to intervene and prevent that amputation especially major amputations prior to their onset. And certainly preventing that second major amputation which you saw several speakers allude to. Patients with limb threatening lesions where they already lost one limb, so critically important for us to pay attention to this. We also saw this slide before indicating the real complexity of this underlying pathology in the diabetic foot. Encompassing multiple facets of neuropathy, the multiple facets of vascular disease as we can see here. And how they can become interrelated and created that what we call high risk foot and trauma on that high risk foot can start the process, the cycle of events going that leads to subsequent diabetic foot ulcer, infection, gangrene and amputation. As I said earlier this morning, it’s incumbent upon us to understand all this underlying metabolic perturbations. So that we can better understand how to treat as well as how to better prevent these problems from occurring initially. So let’s go back to more recent literature. This is one of my favorite classical studies and I’d say it’s a landmark studies at least by Roger Pecoraro who came out of the Seattle VA. This was published in 1990 in diabetes care where he looked at the pathways of diabetic limb amputation using the Rothman model of component and sufficient causes. So Rothman was one of my professors at the Harvard School of Public Health so I took this to be particularly insightful. Why? Because it’s very, very simplistic in its approach. Looking at the possible component causes, we could see these various component causes but when one or more of this component – essential underlying components come together to complete a puzzle chain, it invariably leads to the outcome of interest. In this case the outcome of interest would be amputation. And what Pecoraro found in this 1990 paper was that the three critical components or the three triads present in the 68% of all the amputations were ulceration, minor trauma and faulty wound healing of that ulceration. So again we see that minor trauma plays a very important role not just in ulceration but also for gangrene, neuropathy. Now we can’t disregard that but remember many patients also have just underlying peripheral arterial disease with or without diabetes. So again very importantly that important triad in this regard is ulceration with faulty wound healing of that ulceration and preceding minor trauma. So if we can intervene in our preventive efforts to prevent that minor trauma i.e. provide for protective shoes, taking callouses. There are opportunities for intervention and prevention early on. The Charcot foot. What Joslin never really spoke about, Charcot foot we’ll be hearing more about this in the next session but we recognize that this is potentially limb threatening problem. Not in on itself, but it’s a marker for premature mortality as we saw this morning but also because a high prevalence of deformity, high prevalence of ulceration which can become infected, develop osteomyelitis and sepsis. So these are certainly limb threatening problem that – not Pecoraro but that Joslin never really mentioned. I don’t know if he ever saw Charcot feet. I believe we saw this before Bailey [phonetic] Rogers published in that good issue of the Journal of Vascular Surgery 2010 was a diabetic foot issue. Well we have this simplified picture which is always good because we can remember this.

[15:04]

And this is the so called stairway to amputation. Not really heaven but the stairway to amputation. So we have the high risk neuropathic foot with or without a PAD at the base of the stairway. We’ve sustained some type of injury whether it be a chronic callous as we see here some type of an injury or where I come from a lot of second, third degree burns. We develop a chronic wound; chronic wound becomes infected with an inadequate offloading and care. Develops gangrene and once we have gangrene developed and obviously we must necessitate an amputation at some level depending upon the adequacy of perfusion. But with this, we also see many possible levels to intervene and there by prevent the consequence of gangrene and amputations. So we need to intervene early and there’s multiple points as you can see here right down from the beginning. If we can prevent that initial injury or treat that wound early or prevent that infection by early treatment, we can prevent the consequence of the culmination or the completion of the causal pathway leading to that gangrene. This paper from Olavola also out of the New England Deaconess Hospital where Joslin practiced. This was published in 2004. Looking at it fairly large database, consecutive major lower extremity amputations 81% of which were diabetic mean age of 67 years or so. We looked at the actuarial overall survival of these patients and we see that the five year overall survival is only about 35%. 35%, so 65% of the patients died over five years. These were all with major amputations. But as you would expect below-knee amputations have a five year survival of about 38%, always a little bit higher than that of above-knee amputation which was a five year survival of only 22.5%. So these are pretty drastic, pretty oppressive findings in a very, very good centers. Now you throw in renal failure into this mix, the five year survival goes way down. So this is in a very good center in Boston where the overall five year survival was only about 35% of these patients. So they die of the amputations itself? No. But they die of the consequences either that preceded that amputation or succeeded that amputation with increased cardiovascular stress and oxygen consumption when walking if they began to walk. Very ominous events can occur after a major limb amputation when you look at it like it’s very tragic consequence. So where to avoid major amputations, we must understand how to better prevent them. And that is by being here, by knowing underlying pathophysiology, aggressive management of these various lesions we’ve been talking about. As well as the primary and secondary prevention of all complications especially these lower extremity complications. Basic tenets of limb salvage 2013 as you’ve heard, multidisciplinary team, treating infection early and aggressively. We’ll talk more about that next session. Treat ischemia through adequate clinical assessment and revascularization. Foot sparing surgery, we’ll also be talking about that. Partial foot amputations, bone resections or reconstructive procedures. Now we can do that whereas Joslin could not back in those days. Good adequate wound care with proper debridement, offloading and judicious use of advance therapies as needed. All of this go on to play in managing these chronic wounds so that we can help prevent major limb loss. Once we have these patients healed we have to practice prevention with a good amputation prevention program. Meaning good podiatry care as Joslin himself recommended back in the early parts of the 20th Century. This was also further expounded upon by the international working group by the updated publication in 2011 where they also recommended education, protective footwear, regular preventive care, prophylactic foot surgery and of course multidisciplinary management, good diabetes control and of course team approach. Again, nothing is new under the sun but now it’s recognized that we must do this and around the world we recognized multidisciplinary management is the key so that each one of the specialties involved can practice more efficiently and with the consort of their other specialist to help formulate appropriate patient-centered treatment plans as we heard.

[20:00]

You must tailor your treatments based on the individual uniqueness of each patient. Just to also stress the enhanced benefits of multidisciplinary management, this is a different paper than we saw earlier. This one comes from Kenan in 2012. This was from Scotland where they’ve done a lot of good work on multidisciplinary management. If we look at the bars, the lighter panel is number of total amputations, the darker blue, minor amputations, and the yellow or major amputations. Right around 2004 they started in this district in Scotland, a multidisciplinary team approach focused on amputation prevention. And from there on, you can see a gradual decrease in the incidence of major amputations sorry here it’s in yellow, a 41% decrease in major amputations over five years. Number of – a total amputations decrease in 29.8% because minor generally stays about the same. So after the institution of a multidisciplinary team approach, they saw significant reductions in the incidence of total and certainly major amputations. So that is the way to manage these types of problems and the VA Centers itself, this is national VA data. Once we’ve started the pack teams, I believe this is back in the fiscal year 2000, we see a rapid dramatic reduction in the incidence of lower extremity amputations in patients with diabetes. This was published by Sang et al. in Diabetes Care 2011. [Indecipherable] [21:46] was also on this. He comes from East New Jersey VA. So it’s in the literature, it’s significant reductions based on multidisciplinary management of these complex patients at their onset. So in summary, I like to leave with words of Joslin and he stated back in 1934. “It is been forced upon me that gangrene is not heaven-sent but is earth borne”. Joslin recognized that gangrene was a consequence of multiple factors many of which could have been prevented. And that if we better understand the underlying pathophysiology i.e. neuropathy, peripheral arterial disease, diabetes control, avoidance of trauma, et cetera, et cetera. We’d be more successful in our prevention efforts so that we can continue to reduce the incidence of lower limb amputation in high risk diabetic patients. Thank you.